We make every effort to ensure the data presented here is accurate based on the best available information currently on file with DEC. It is therefore subject to change as new information becomes available. We recommend contacting the assigned project staff prior to making decisions based on this information.

Problems/Comments

On October 31, 1991 a 2,500 gallon diesel UST and its associated dispenser pump was removed. The following day a 3,000 gallon heating oil UST was removed from the same site. The sizes of the excavations were limited to the extent necessary to remove the tanks. Additional soil was not removed. Approximately 20 cubic yards of soil was excavated during the removal of the USTs. Soil was taken to Alaska Sand and Gravel for thermal processing. Soil samples collected from the limits of the excavation from the diesel tank indicated that total petroleum hydrocarbons (TPH) were present in concentrations up to 15,300 mg/kg. Benzene was not detected in this excavation. Two samples were collected from the excavation of the heating oil tank. TPH was present in both samples at 539 and 937 mg/kg. Benzene was present in one sample at a concentration of 0.035 mg/kg. A PVC pipe gallery was installed around the perimeter of each excavation. The excavations were backfilled with clean fill and remediation activities did not commence again until September 2003.
In March 1996 Science Applications International Corporation (SAIC) under contract to EPA, released a RCRA Facility Assessment Report of ARRC properties in the Lower Ship Creek Basin. EPA designated the Former Bridges and Building Shop located at 825 Whitney as Solid Waste Management Unit (SWMU) 28. SWMU 28 was reported to have waste oil and solvent drums stored prior to being transferred to railcars or sent off site.
On September 11, 2003 soil was excavated at the location of the former underground tanks and stockpiled on site to the west of the excavation. A PID was used to determine the presence of hydrocarbon contamination and the stockpiles were segregated accordingly. Soil removal continued until groundwater was reached at approximately 10 feet below ground surface. A total of 1,337 cubic yards of impacted soils was transported to Alaska Soil Recycling September 25-26, 2003. Soil samples taken from the limits of the excavation indicated that diesel range organics (DRO) contamination was still present in 3 of 14 samples in concentrations up to 447 mg/kg. Trichloroethane (TCE) was present in four samples in concentrations up to 0.642 mg/kg. Three test pits were dug at SWMU 28 to depths between one and three feet below ground surface. TCE was present in a sample taken from the test pits at the former SWMU 28 at 0.439 mg/kg. Soil stockpiles associated with the excavation and test pits were removed and transported to Alaska Soil Recycling (ASR). The soil treated at ASR was determined to meet DEC cleanup levels and was returned to the site. The treated soil was used in combination with the clean stockpiles as backfill for the excavation and test pits. The subject property is currently being used as the new Anchorage Operations Center and adjacent parking lot for the Alaska Railroad Corporation.

A heating oil tank and diesel tank was removed in 1991. A Solid Waste Management Unit is present on the property. TCE and DRO is still present in the location of the former tanks and SWMU. ARRC Business Operations Building has been built over half of the contaminated area.

Sarah Cunningham

8/11/2005

GIS Position Updated

TopoZone Pro was used in conjunction with Anchorage Area Atlas. A huge size high resolution aerial photo was used at a 1:3,333 scale with no topo base map. NAD83.

Sarah Cunningham

8/11/2005

Update or Other Action

Research on current site status concludes TCE and DRO contamination is still present at site.

Sarah Cunningham

8/11/2005

Site Ranked Using the AHRM

Site received a medium priority. Site is located 700 feet north of Ship Creek.

Sarah Cunningham

11/2/2007

Exposure Tracking Model Ranking

intial ranking completed

Grant Lidren

12/3/2007

Institutional Control Record Established

Based on the Record Of Decision , ADEC has determined that no further remedial action will be required at this site subject to the following conditions: First, a Notice of Environmental Contamination will be recorded on the ADEC database to document that there is residual contamination remaining on site above the most stringent ADEC cleanup level. Second A proposal to transport soil off site requires ADEC approval in accordance with 18 AAC 78.274(b)

Grant Lidren

12/3/2007

Conditional Closure Approved

The Department of Environmental Conservation, Contaminated Sites Program (ADEC) has completed review of the Soil Excavation and Site Assessment Report prepared by HartCrowser in January 2004 for the excavation of soils associated with the removal of two underground storage tanks (USTs) at the Alaska Railroad Corporation (ARRC) Operations Building. Based on the information provided in this report, ADEC has determined that the soil contamination remaining on site exceeds the most stringent ADEC soil cleanup levels, but does not pose an unacceptable risk to human health or the environment. Site conditionally closed with instutional controls.

Grant Lidren

6/13/2012

Update or Other Action

Staff changed from Grant Lidren to IC Unit.

Kristin Thompson

7/9/2012

Institutional Control Compliance Review

IC review conducted.

Evonne Reese

7/9/2012

Institutional Control Record Removed

This site meets the 2009 closure policy therefore ICs can be removed. The default requirement of no offsite transport of soil or groundwater from this site is still applicable.

Per a communication from ARRC on this date "[t]he ARRC Anchorage Operation Center ( AOC) air system is set at a positive pressure of 0.8 inches. The air intake for the building is located on the roof and over 30 feet from the ground. Heating for the building is radiant heating set within the concrete. The concrete floors have been epoxy coated prior to installing tiles carpet or other floor covering.

Grant Lidren

Contaminant Information

Name

Level Description

Media

Comments

DRO

Between Method 2 Migration to Groundwater and Human Health/Ingestion/Inhalation

Soil

Control Type

Type

Details

No ICs Required

Requirements

Missing Location Data

Because the GIS location data for this site has not been entered, we cannot direct you to its position on the map. Click "Continue" to proceed to the Contaminated Sites Web Map or "Close" to return to the site report.